The present disclosure relates generally to bonded structures and more particularly to brazed metallic workpieces.
It is known to make a sandwich of metal sheets, the center core sheet including peaks and valleys. Such sheets are bonded together with adhesive in production. Examples of such a sandwich are disclosed in commonly owned U.S. Pat. No. 8,835,016 entitled “Optimal Sandwich Core Structures and Forming Tools for the Mass Production of Sandwich Structures” which issued to Ebnoether on Sep. 16, 2014, and U.S. Pat. No. 7,648,058 entitled “Formed Metal Core Sandwich Structure and Method and System for Making Same” which issued to Straza on Jan. 19, 2010, both of which are incorporated by reference herein. These patents have been significant improvements in the industry. Furthermore, these patents mention brazing as a method to bond together the sandwich sheets. There is room for additional improvement, however, in developing brazing machines and methods which are cost effective and efficient in high volume manufacturing of large production parts.
It is also known to braze zinc coated steel sheets. For example, laser soldering and arc welding approaches are discussed in Wilden et al., “Low Temperature Brazing of Zinc Coated Steel and Steel/Aluminum Joints by Setting ZnAl-Alloys as Brazing Material,” Proceedings of the 3rd International Brazing and Soldering Conference (Apr. 24-26, 2006). Nevertheless, such procedures and equipment are not well suited for cost effective and high volume production manufacturing, especially involving large workpiece sheets.